Although lithium, and other alkali ion, batteries are widely utilized and studied, many of the chemical and mechanical processes that underpin the materials within, and drive their ...degradation/failure, are not fully understood. Hence, to enhance the understanding of these processes various ex situ, in situ and operando characterization methods are being explored. Recently, electrochemical atomic force microscopy (EC‐AFM), and related techniques, have emerged as crucial platforms for the versatile characterization of battery material surfaces. They have revealed insights into the morphological, mechanical, chemical, and physical properties of battery materials when they evolve under electrochemical control. This critical review will appraise the progress made in the understanding batteries using EC‐AFM, covering both traditional and new electrode–electrolyte material junctions. This progress will be juxtaposed against the ability, or inability, of the system adopted to embody a truly representative battery environment. By contrasting key EC‐AFM literature with conclusions drawn from alternative characterization tools, the unique power of EC‐AFM to elucidate processes at battery interfaces is highlighted. Simultaneously opportunities for complementing EC‐AFM data with a range of spectroscopic, microscopic, and diffraction techniques to overcome its limitations are described, thus facilitating improved battery performance.
Electrochemical atomic force microscopy is becoming an important platform for the characterization of the electrode–electrolyte boundary in alkali‐ion batteries. However, as it is increasingly used to reveal details of battery morphological, mechanical, and chemical evolution, it is essential that the relevance of these discoveries to industry‐relevant batteries is considered and contrasted against discoveries made using alternative tools.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Median adhesion forces of tritiated tungsten micro-particles deposited on a glass substrate were successfully determined using an aerodynamic method (AM) which is presented in this paper. The ...original aerodynamic device built for these experiments has been carefully characterized in terms of friction velocities allowing to quantify aerodynamic torque exerted on the particles and to deduce median adhesion forces thanks to a force balance approach. Using the same particle/surface systems (non-radioactive tungsten particles in contact with a glass substrate), distribution of adhesion forces were obtained using AFM for comparison with the AM. The results show a good agreement between the two techniques which allowed to validate the AM. Furthermore, a precise description of the root-mean square roughness (rms) distribution of the glass substrate made it possible to compare the experimental results with different analytical adhesion force models. Integrating the rms roughness distribution of the substrate into the model of Rabinovich et al. showed the best agreement with the present experiments capturing most of the adhesion forces of 10µm to 18µm diameter tungsten particles. Moreover, the method developed in this work made it possible to show that the electrostatic image force arising from the self-charging of tritiated tungsten particles has a negligible contribution in the adhesion of the particles for the studied configuration.
•An original aerodynamic method (AM) is proposed to measure adhesion force of radioactive particles.•The new AM has been successfully compared to adhesion force distributions obtained by AFM.•Influence of surface roughness and radioactivity on particle adhesion have been addressed quantitatively.•Experimental results are compared with various analytical adhesion models from the literature.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Pit initiation in quenching and partitioning processed martensitic stainless steels was investigated.•The corrosion resistance of Q&P steels is controlled mainly by the presence of inclusions.•The ...lower surface potential at MnS results in selective dissolution of the MnS site.•The higher surface potential at TiN results in selective dissolution at the interface between TiN and the matrix.
The present article investigates the influence of chemical composition and phase fractions on the corrosion behaviour of industrially produced quenching and partitioning (Q&P) martensitic stainless steels. Localised corrosion was analysed by scanning Kelvin probe force microscopy (SKPFM) and scanning electrochemical microscopy (SECM) in 3.5 wt.% NaCl solution. SKPFM revealed a Volta-potential difference of around 40 mV between inclusions and the matrix, which is larger than the Volta potential variations within the matrix. This difference in surface potential is a driving force for selective dissolution (corrosion initiation) at inclusions and inclusion/matrix interfaces. SECM detected early pitting initiation, particularly in alloys containing MnS and TiN inclusions. Results suggest that pitting initiation and propagation occur at those specific regions. This study emphasised that irrespective of chemical composition and phase fraction, localised corrosion initiation in Q&P-processed martensitic stainless steels is predominantly governed by the presence of inclusions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Electric double layers (EDLs), occurring ubiquitously at solid–liquid interfaces, are critical for electrochemical energy conversion and storage processes such as capacitive charging and redox ...reactions. However, to date the molecular-scale structure of EDLs remains elusive. Here we report an advanced technique, electrochemical three-dimensional atomic force microscopy (EC-3D-AFM), and use it to directly image the molecular-scale EDL structure of an ionic liquid under different electrode potentials. We observe not only multiple discrete ionic layers in the EDL on a graphite electrode but also a quasi-periodic molecular density distribution within each layer. Furthermore, we find pronounced 3D reconfiguration of the EDL at different voltages, especially in the first layer. Combining the experimental results with molecular dynamics simulations, we find potential-dependent molecular redistribution and reorientation in the innermost EDL layer, both of which are critical to EDL capacitive charging. We expect this mechanistic understanding to have profound impacts on the rational design of electrode–electrolyte interfaces for energy conversion and storage.
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IJS, KILJ, NUK, PNG, UL, UM
Abrupt aggregation of amyloid β1‐42 (Aβ) peptide is a hallmark of Alzheimer's disease (AD), a severe pathology that affects more than 44 million people worldwide. A growing body of evidence suggests ...that lipids can uniquely alter rates of Aβ1‐42 aggregation. However, it remains unclear whether lipids only alter rates of protein aggregation or also uniquely modify the secondary structure and toxicity of Aβ1‐42 oligomers and fibrils. In this study, we investigated the effect of phosphatidylcholine (PC), cardiolipin (CL), and cholesterol (Chol) on Aβ1‐42 aggregation. We found that PC, CL and Chol strongly accelerated the rate of fibril formation compared to the rate of Aβ1‐42 aggregation in the lipid‐free environment. Furthermore, anionic CL enabled the strongest acceleration of Aβ1‐42 aggregation compared to zwitterionic PC and uncharged Chol. We also found that PC, CL and Chol uniquely altered the secondary structure of early‐, middle‐ and late‐stage Aβ1‐42 aggregates. Specifically, CL and Chol drastically increased the amount of parallel β‐sheet in Aβ1‐42 oligomers and fibrils grown in the presence of these lipids. This caused a significant increase in the toxicity of Aβ : CL and Aβ : Chol compared to the toxicity of Aβ : PC and Aβ1‐42 aggregates formed in the lipid‐free environment. These results demonstrate that toxicity of Aβ aggregates correlates with the amount of their β‐sheet content, which, in turn, is determined by the chemical structure of lipids present at the stage of Aβ1‐42 aggregation.
Abrupt aggregation of amyloid β1‐42 peptide is the expected underlying molecular cause of Alzheimer disease, a severe pathology that affects millions of people around the world. We discovered that phospholipids and cholesterol could uniquely alter rates of amyloid β1‐42 aggregation. Furthermore, in the presence of phospholipids and cholesterol amyloid β1‐42 formed structurally different oligomers are fibrils that exerted significantly greater cell toxicity compared to those formed in the lipid‐free environment.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
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•The orthorhombic structure of EuCrO3 is more stable compared to the cubic one.•The Orthochromite EuCrO3 exhibits a P-type direct semiconductivity behaviour.•EuCrO3 is a G-type ...anti-ferromagnetic with a y-axis easy magnetization (AFM-Gy) with a Neel temperature of 195 K.•The Orthochromite EuCrO3 is a promising candidate for photovoltaic, thermoelectric, and magnetic refrigeration devices.
A comparative study of the structural and electronic properties of the orthorhombic and cubic structure of EuCrO3 has been performed in this manuscript. The stability of the orthorhombic structure with respect to the cubic one has been studied. The calculated optical band gap energies were determined to be 2.09 eV, 1.95 eV and 2.02 eV along the 100, 010, and 001 directions, respectively, and are in good agreement with previous work. The studied material exhibits the behavior of a P-type semiconductor. EuCrO3 is a Gy-antiferromagnetic semiconductor with a partial magnetic moment of 2.18 µB induced by the 3d3 orbital of Cr3+ electrons and a Neel temperature of 195 K. This behavior is attributed to the super-exchange mechanisms between Cr3+-Cr3+ cations via O2– ions. Optical, thermoelectric and magnetocaloric studies revealed that europium chromite EuCrO3 is a promising candidate for photovoltaic, thermoelectric, and magnetic refrigeration devices.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study provides analyses of the Atomic Force Microscope (AFM) rupture length, which is the longest distance in the Z-direction where the adhesion is obtained by release force curves. Clear XY ...rupture length images were obtained from the results. In this paper, we showed that there is a difference in the distribution of adhesion force vs rupture length plot on the surface of silica particles with different surface treatment materials, and that clear rupture length images of LiB binder and polymer film with a sea-island structure could be obtained. From these, we concluded that the AFM rupture length can be a valid parameter for material surface as well as the adhesion force.
•Electrochemical tests were done on mild steel samples in 0.5 M sulfuric acid solution.•Maximum corrosion inhibition efficiency (>95%) was obtained with 500 mg/L.•Adsorption of phytochemicals was ...studied by DFT and MC simulations.•SEM and AFM verified the surface adsorption of P. somniferum.
The corrosion resistance of iron alloy in 0.5 M sulphuric acid was checked in the presence and absence of Papaver somniferum (P. somniferum ) seed extract. Notably, P. somniferum showed 95% corrosion resistance efficiency at 500 mg/L concentration. The adsorption of this inhibitor follows the Langmuir isotherm indicating its monolayer formation on the surface of iron alloy. The potentiodynamic experiments indicated its nature as mixed type of inhibition behaviour. The SEM and AFM techniques were used to study the protective layer on iron alloy. FT-IR with ATR confirmed various functional groups containing heteroatoms present in phytochemicals and formed complex with iron respectively. Theoretical studies were given as a valuable report to understand the comparative adsorption of phytochemical. All acquired outcomes confirmed that P. somniferum seed extract act as an efficient corrosion inhibitor.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
HfOx‐based memristor has been studied extensively as one of the most promising memories for the excellent nonvolatile data storage and computing‐in‐memory capabilities. However, the resistive ...switching mechanism, relying on the formation and rupture of conductive filaments (CFs) during device operations, is still under debate. In this work, the CFs with different morphologies after different operations—forming, set, and reset—are clearly revealed for the first time by 3D reconstruction of conductive atomic force microscopy (c‐AFM) images. Intriguingly, multiple CFs are successfully observed in HfOx‐based memristor devices with three different resistive states. CFs after forming, set, and reset exhibit the typical morphologies of hourglass, inverted‐cone, and short‐cone, respectively. The rupture location of CFs after the reset operation is also observed clearly. These findings reveal the microscopic behaviors underlying the resistive switching, which could pave the road to design and optimize oxide‐based memristors for both memory and computing applications.
Conductive filaments (CFs) with different morphologies after forming, set, and reset operations are clearly revealed in HfOx‐based memristors by the 3D reconstruction of c‐AFM technique. Multiple conductive filaments are successfully observed in the devices with three different resistive states. The rupture location of CFs after reset is also observed clearly.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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